This invention relates to toilet systems that utilize fluid pressure from a water supply to flush waste material from the toilet bowl to a waste-holding tank and in particular relates to such toilet systems in which the flushing liquid is not recirculated and which utilize fresh water for each flush to rinse the toilet bowl and assist in the evacuation of the waste matter from the bowl.
This system using fluid pressure for flushing is especially desirable in applications where the use of water and gravity to flush waste from the bowl are restricted by the limited availability of large quantities of water for use in the flushing operation. Examples of situations in which water supplies are limited include commercial passenger aircraft and other commercial conveyances, such as trains and boats, and also in vacation and resort dwellings that are located in remote areas with no municipal water system.
Previously, most toilet systems used in commercial aircraft have been of the recirculating type wherein the flushing liquid and waste material removed from the toilet bowl pass through a filtering system and the flushing liquid is recycled for use in later flushing of the toilet bowl. While typical recirculating flushing systems serve the purpose, they require a large-capacity filtration system in order to separate the flushing liquid from solid waste, thereby permitting the reuse of the flushing liquid. These toilets also require a pump and an electric motor for flushing. Such filtration systems and motor-pump assemblies require frequent maintenance and servicing.
On the other hand, the use of a freshwater flushing eliminates both the filtration and motor-pump problems. The most logical source of flushing liquid for the commercial aircraft is the potable water supply, since each aircraft is generally equipped with one. However, use of the potable water supply for toilet flushing imposes a strict requirement that each flush use a minimum amount of water in order to conserve storage volume and minimize water weight in the aircraft. Also, to avoid complications in pressure regulation and valving, it is desirable that the pressure required of the flushing liquid be no higher than the potable water pressure so that the same valving and pressure-regulating equipment can be used for both the potable water and the flushing water.